草莓棒孢叶斑病的病原菌鉴定及其对9种杀菌剂的敏感性

对采自山东省诸城市草莓叶斑病发病叶片上的病原菌进行了分离及鉴定，通过室内人工接种法确定该病原菌的致病性，并采用菌丝生长速率法测定了其对双苯菌胺等9种杀菌剂的敏感性。结果表明:形态学结合ITS系统发育分析确定该病原菌为多主棒孢霉Corynespora cassiicola。室内毒力测定结果显示:9种供试杀菌剂中，双苯菌胺对C. cassiicola菌丝生长有很强的抑制作用，其平均EC₅₀值为 (0.27 ± 0.18) μg/mL，可作为防治草莓叶斑病的首选药剂；其次为氟环唑、腈菌唑、咪鲜胺、苯醚甲环唑、嘧菌酯和戊唑醇，平均EC₅₀值分别为 (0.66 ± 0.21)、(0.85 ± 0.25)、(1.4 ± 1.2)、(1.8 ± 0.3)、(3.8 ± 3.0) 和 (4.5 ± 2.6) μg/mL；而该病原菌对百菌清与代森锰锌的敏感性最低。研究结果可为草莓棒孢叶斑病的化学防治提供参考。

Pathogen identification of Corynespora leaf spot on strawberry and its sensitivity to nine fungicides

The pathogen of a new strawberry leaf spot disease collected from Zhucheng city, Shandong Province was isolated and identified. Its pathogenicity was determined by indoor inoculation. Its susceptibility to 9 fungicides such as SYP-14288 was determined by mycelial growth rate method. The results showed that the pathogen was Corynespora cassiicola according to the morphological analysis and ITS phylogenetic analysis. The results also showed that SYP-14288 had a strong inhibitory effect on the mycelia growth of C. cassiicola, with an average EC₅₀ value of (0.27 ± 0.18) μg/mL, which could be used as the first choice for the control of strawberry leaf spot disease. The mean of EC₅₀ values were (0.66 ± 0.21) μg/mL, (0.85 ± 0.25) μg/mL, (1.4 ± 1.2) μg/mL, (1.8 ± 0.3) μg/mL, (3.8 ± 3.0) μg/mL and (4.5 ± 2.6) μg/mL for epoxiconazole, myclobutanil, prochloraz, difenoconazole, azoxystrobin and tebuconazole, respectively. Chlorothalonil and mancozeb had the lowest toxicity. The results have provided a reference for the control of Corynespora leaf spot on strawberry.